An EL-Diver (EL (エル) ダイバー EL Daibā (pronounced as Ellu Diver)?), shortened from Electronic Lifeform Diver, is an electronic lifeform born in the GBN. There are currently 87 known EL-Divers in existence.
The birth of EL-Divers from the massive amount of data in GBN was first theorized by Ms. Tori. The first known EL-Diver, Sarah, was discovered by Force Build Divers members Riku Mikami and Yukio Hidaka. However, her identity as an EL-Diver wasn't known until the GBN administration conducted an investigation following the Nadeshiko-athalon incident. Though viewed as a threat by the administration in the beginning, following the fight for Sarah's life during the 2nd Coalition of Volunteers battle, the EL-Divers became more widely accepted and they live in real life under the administration's supervision. Some EL-Divers, such as Sarah and May, are granted special Gunpla bodies known as "Mobile Dolls" that mimic their looks and are made by Koichi Nanase and Tsukasa Shiba. The Mobile Dolls allow the El-Divers to exist outside of GBN, allowing them to move and interact with the human world (albeit at a much reduced scale), and also act as registered Gunpla they can use in GBN.
Two years after the 2nd Coalition of Volunteers battle, it was discovered that GBN has a connection to the extraterrestrial planet Eldora and an alien race that previously existed on this planet might have played a role in how EL-Divers came to exist. Cuadorn, a sacred beast of Eldora, told the Force BUILD DiVERS members that following a series of conflicts that devastated the planet eons ago, some of the Ancients (inhabitants of the planet then) departed to elsewhere as data lifeforms. Ms. Tori eventually learnt of this information and recalled that at some point during the development of GBN, the game suffered what seemed to be a hacking attempt, with the source of the attack being unknown. She speculated that the "attack" might have been the Ancient’s electronic presences entering the system, and this could have been the final triggering factor that enabled life to be born in GBN.
Around the same time, it was also revealed that data from deceased/deleted EL-Diver (or other data lifeform that managed to enter GBN) returns to GBN's data stream, and some of this data may combine with other factors to result in the birth of a new EL-Diver. Leftover data from this process can manifest in the form of an accessory that the new EL-Diver is born with. This accessory seems to be related in some manner to the deceased/deleted EL-Diver.